1. Field of the Invention
This invention generally relates to devices for processing data to be manually entered and, more particularly, to a keyboard for accurately and reliably manually entering data into devices of miniature dimensions.
2. Description of Related Art
Electronic data processing devices having manual entry keyboards for inputting data are, of course, well known. Although generally satisfactory for their intended purposes, experience has shown that when the individual keys are situated too close together, e.g. on the order of 5/8" or less, often when a user uses his or her forefinger to depress one key, an adjacent key is inadvertently depressed at the same time, thereby causing data entry errors. This key-crowding problem is tolerated on miniature data processing devices, such as watch-calculator devices, where there simply is not much available room to space the keys apart from one another by distances sufficient to avoid the aforementioned problem of inadvertently depressing two keys at a time. The too-close spacing of the keys is also tolerated on larger devices where there is a design requirement for a multitude of alpha-numeric and function keys, such as on a computer-type typewriter-like keyboard, where there is insufficient room available to accommodate all such keys on a reasonably-sized keyboard housing unless all such keys are crowded together.
The key-crowding problem is typically dealt with in the art by either designing the keyboard housing to be oversized, or, in those applications where the keyboard housing must be of miniature size, e.g. in a watch-calculator device, by providing the user with a stylus to reliably depress one key at a time. This, however, is not a practical solution, because the stylus is often misplaced and not available for use when necessary. Many users resort to using a ballpoint pen or pencil to depress keys on a watch-calculator device, and often the resulting ink and pencil smears create a mess.